Computerized Mapping Makes It Easier To Take World's Picture

PHILADELPHIA — Relying on a commercial road map, medics in the ambulance rushing through the Pittsburgh neighborhood got lost as they hunted for mapped streets that did not exist.

What should have been a 10-minute run took half an hour, and a woman stricken by a heart attack died.

A repetition of that tragedy of a year ago may have less of a chance of occurring in the future.

At month's end Pittsburgh will switch on a computerized mapping system that will almost instantly give public-safety dispatchers directions to callers' locations. And it will contain no "paper" streets - ones yet to be built.

The computerized system is a prime example of the emerging industry of sophisticated mapping that is moving into wider use by government and business.

Indeed, the City of Philadelphia by next year plans to purchase a similar mapping system that can be used, among other things, for plotting sewer and water systems and tracking tax assessments.

Businesses in the Philadelphia area also are using computerized mapping to advise retailers where to open stores and to help hospitals decide where services are needed.

The industry will get a boost in the next few years as the U.S. Census Bureau releases its new mapping system, called TIGER, through which it will gather population, housing and economic statistics in the 1990 census.

The system is immensely increasing the bureau's productivity, said Philip Lutz, geographic coordinator in the Philadelphia regional census office.

"TIGER really is quite a radical innovation at the Census Bureau," said Donald F. Cooke, president of Geographic Data Technology Inc. of Lyme, N.H., which produces computerized mapping software.

In 1980, as many as 1,500 clerks worked in a processing center in Indiana updating and correcting acres of census maps by hand.

Today, the maps can be changed with the flick of a computer key. And, for the first time, the demographic data from the census will be integrated into the mapping system.

Census Bureau field workers, who have been checking addresses and streets throughout the nation in recent months, use printouts of the maps to write in the names of new housing developments or to correct information.

When the maps are returned to the bureau, technicians working at high-resolution color computer screens simply run computer mouses over the corrected maps to record the changes in the permanent computer files.

A technician at the regional census office last week was doing just that to a map of Montour County north of Harrisburg, Pa. A bright blue stripe proved to be the Susquehanna River, a bright purple splotch was a graveyard, and a tiny red dot - when the computer zoomed in - was a school.

Uses for such computerized mapping - called Geographic Information Systems - have only begun to emerge.

"The question would be how we aren't using it," said Harry W. Rivkin, president of Integrated Database Technologies Inc. of Blue Bell, Pa. "Nobody yet has any idea of what the end applications to this will be." Rivkin's firm uses GIS to help companies select sites and map out sales territories.

The Environmental Protec tion Agency, for instance, is using GIS to monitor potential pollution of drinking water and outbreaks of radon gas, and distribution companies are using GIS to find the most efficient routes for their trucks.

Many separate data bases - showing everything from disease statistics to hazardous-waste dumps and a particular magazine's subscribers - can be integrated into one mapping system and laid out on the map separately or together by computer. The maps will pull together otherwise disparate statistics to help businesses, governments and others analyze the information in a comprehensive package.

For example, in the past, thousands of dollars and hundreds of hours might have gone into producing one set of aerial photographs, site-selection maps and transparent overlays for use by a retailer who wanted to open a new store. Now hundreds of scenarios for dozens of users can be produced almost instantaneously from the computerized maps.

At the Census Bureau, a big issue is the updating of TIGER files. "What is going to be done to maintain this product once the census is over?" asked geographer Lutz at the bureau.

Private industry probably has the answer: The profit motive will prompt companies to take over the updating. Cooke at Geographic Data said his firm was part of a joint venture aiming to keep TIGER up to date for clients between 10-year censuses.

Jack Dangermond, whose company, Environmental Systems Research Institute Inc. of Redlands, Calif., is a leader in computerized mapping, said TIGER would become part of the nation's infrastructure, like its highway system.